Sh256加密和byte数组转换为16进制字符串

/**
     * SHA加密
     *
     * @param strSrc
     *            明文
     * @return 加密之后的密文
     */
    public static String shaEncrypt(String strSrc) {
        MessageDigest md = null;
        String strDes = null;
        byte[] bt = strSrc.getBytes();
        try {
            md = MessageDigest.getInstance("SHA-256");// 将此换成SHA-1、SHA-512、SHA-384等参数
            md.update(bt);
            strDes = bytes2Hex(md.digest()); // to HexString
        } catch (NoSuchAlgorithmException e) {
            return null;
        }
        return strDes;
    }

    /**
     * byte数组转换为16进制字符串
     *
     * @param bts
     *            数据源
     * @return 16进制字符串
     */
    public static String bytes2Hex(byte[] bts) {
        String des = "";
        String tmp = null;
        for (int i = 0; i < bts.length; i++) {
            tmp = (Integer.toHexString(bts[i] & 0xFF));
            if (tmp.length() == 1) {
                des += "0";
            }
            des += tmp;
        }
        return des;
    }

    /**
     * 利用java原生的类实现SHA256加密
     * @param str 加密后的报文
     * @author
     */
    public static String getSHA256(String str) {
        MessageDigest messageDigest;
        String encodestr = "";
        try {
            messageDigest = MessageDigest.getInstance("SHA-256");
            messageDigest.update(str.getBytes("UTF-8"));
            encodestr = byte2Hex(messageDigest.digest());
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return encodestr;
    }

    /**
     * 将byte转为16进制
     *
     * @author CaoLu.
     */
    private static String byte2Hex(byte[] bytes) {
        StringBuffer stringBuffer = new StringBuffer();
        String temp = null;
        for (int i = 0; i < bytes.length; i++) {
            temp = Integer.toHexString(bytes[i] & 0xFF);
            if (temp.length() == 1) {
                // 1得到一位的进行补0操作
                stringBuffer.append("0");
            }
            stringBuffer.append(temp);
        }
        return stringBuffer.toString();
    }